CORE C: RECRUITMENT, RETENTION AND COHORT MANAGEMENT ABSTRACT The Recruitment, Retention and Cohort Management Core will coordinate all aspects of creating and maintaining an enrolled Longitudinal Study Population of 10,000 dogs. In this complex nationwide study, effective communication with owners and veterinarians across diverse sites is paramount to facilitate accurate and timely submission of data in many forms. To ensure success, this core will be governed by the Chief Veterinary Officer, Dr. Kate Creevy, at Texas A&M College of Veterinary Medicine & Biomedical Sciences along with Dr. Daniel Promislow, the PI of the U19 Research Program and co-Investigator for this Core. The Recruitment, Retention and Cohort Management Core will achieve its overall goals through a set of three specific aims. Specific Aim 1 will construct, manage and maintain a cohort with sufficient power to address the central hypotheses of the U19. This will include development of cohorts that include an appropriate balance of breed, sex and age for the study segments, and that fairly represent the diversity of dog owners in the United States. The second Specific Aim will develop and maintain protocols to make it possible to collect medical records data and enrolled dog clinical measurements and assays with minimal burden on participants. Core C will create and distribute paper and electronic recruitment materials to veterinarians, dog owners and interested groups; it will coordinate enrollment requests and select participants for all U19-related studies; it will ensure Informed Consent is obtained from owners and archived; and it will monitor timely completion of study- related physical examinations, questionnaires and laboratory assessments and submission of data generated by these events. Finally, Specific Aim 3 will create the infrastructure needed to respond to questions and concerns from participating owners and veterinarians regarding completion of study-related tasks; and to oversee ongoing communication with and among participants.